[SPARK-34280] Avoid migrating un-needed shuffle files

• Type: Improvement
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 3.1.0, 3.1.1, 3.1.2, 3.2.0
• Component/s: Spark Core
• Assignee: Unassigned
• Reporter: Holden Karau
• Created: 28/Jan/21 20:04
• Updated: 31/Jan/21 05:12

Description

In Spark 3.1 we introduced shuffle migrations. However, it is possible that a shuffle file will still exist after it is no longer needed. I've only observed this in a back port branch with SQL, so I'll do some more digging.